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101.
The photoconductivity of a two-dimensional electron gas in the far IR range in a quantizing magnetic field is investigated
for samples in Corbino geometry, which eliminates transport by edge states. It is shown that the photoelectric effect is more
than simply the bolometric response of the system, acquiring a component induced by the direct involvement of photoexcited
carriers in low-energy scattering processes.
Fiz. Tekh. Poluprovodn. 33, 976–978 (August 1999) 相似文献
102.
B. V. Volovik A. F. Tsatsul’nikov D. A. Bedarev A. Yu. Egorov A. E. Zhukov A. R. Kovsh N. N. Ledentsov M. V. Maksimov N. A. Maleev Yu. G. Musikhin A. A. Suvorova V. M. Ustinov P. S. Kop’ev Zh. I. Alferov D. Bimberg P. Werner 《Semiconductors》1999,33(8):901-905
When an array of strained InAs nanoislands formed on a GaAs surface is overgrown by a thin (1–10 nm) layer of an indium-containing
solid solution, stimulated decomposition of the solid solution is observed. This process causes the formation of zones of
elevated indium concentration in the vicinity of the nanoislands. The volume of newly formed InAs quantum dots increases as
a result of this phenomenon, producing a substantial long-wavelength shift of the photoluminescence line. This effect is enhanced
by lowering the substrate temperature, and it depends weakly on the average width of the band gap of the solid solution. The
indicated approach has been used successfully in achieving room-temperature emission at a wavelength of 1.3 μm.
Fiz. Tekh. Poluprovodn. 33, 990–995 (August 1999) 相似文献
103.
Zhao Zhen D. A. Bedarev B. V. Volovik N. N. Ledentsov A. V. Lunev M. V. Maksimov A. F. Tsatsul’nikov A. Yu. Egorov A. E. Zhukov A. R. Kovsh V. M. Ustinov P. S. Kop’ev 《Semiconductors》1999,33(1):80-84
The optical properties of structures containing InGaAs quantum dots in GaAs and AlGaAs matrices grown by molecular-beam epitaxy
are investigated. It is shown that increasing the In content in the quantum dots has the effect of raising the energy of carrier
localization and increasing the energy distance between the ground state and the excited states of carriers in the quantum
dots. An investigation of the influence of postgrowth annealing on the optical properties of the structures shows that the
formation of vertically coupled quantum dots and the use of a wide-gap AlGaAs matrix enhances the thermal stability of the
structures. Moreover, high-temperature (830 °C) thermal annealing can improve the quality of the AlGaAs layers in structures
with vertically coupled InGaAs quantum dots in an AlGaAs matrix. The results demonstrate the feasibility of using postgrowth
annealing to improve the characteristics of quantum dot lasers.
Fiz. Tekh. Poluprovodn. 33, 91–96 (January 1999) 相似文献
104.
O. V. Nekrutkina S. V. Sorokin V. A. Kaigorodov A. A. Sitnikova T. V. Shubina A. A. Toropov S. V. Ivanov P. S. Kop’ev G. Reuscher V. Wagner J. Geurts A. Waag G. Landwehr 《Semiconductors》2001,35(5):520-524
Submonolayer cyclic epitaxy was used for the first time to obtain a bulk layer of BeCdSe solid solution 100 nm thick with a Be content close to 46%, which corresponded to the composition lattice-matched to the GaAs substrate. In addition, low-temperature lasing at a wavelength of 460 nm with a threshold power density of about 40 kW/cm2 in a structure with multiple ZnSe/BeCdSe quantum wells was also attained for the first time. The band-bending parameter in the BeCdSe solid solutions was estimated at 4.5 eV. 相似文献
105.
A. N. Ionov P. G. Baranov B. Ya. Ber A. D. Bulanov O. N. Godisov A. V. Gusev V. Yu. Davydov I. V. Il’in A. K. Kaliteevskiĭ M. A. Kaliteevskiĭ A. Yu. Safronov I. M. Lazebnik H. -J. Pohl H. Riemann N. V. Abrosimov P. S. Kop’ev 《Technical Physics Letters》2006,32(6):550-553
Phosphorus-doped silicon 30Si monoisotope samples with a highly homogeneous impurity distribution at a concentration of 5 × 1016 cm?3 were obtained for the first time by means of neutron transmutation doping. 相似文献
106.
Employing a test structure, velocity overshoot in silicon inversion layers is observed at room temperature. For channel lengths longer than 0.3 μm, the velocity/field relation follows the well-known behavior with no channel length dependence. The first indication of velocity overshoot is seen at a channel length of 0.22 μm, while at L =0.12 μm, drift velocities up to 35% larger than the long-channel value are measured 相似文献
107.
G. E. Cyrlin V. N. Petrov V. G. Dubrovskii Yu. B. Samsonenko N. K. Polyakov A. O. Golubok S. A. Masalov N. I. Komyak V. M. Ustinov A. Yu. Egorov A. R. Kovsh M. V. Maximov A. F. Tsatsul’nikov B. V. Volovik A. E. Zhukov P. S. Kop’ev N. N. Ledentsov Zh. I. Alferov D. Bimberg 《Semiconductors》1999,33(9):972-975
The mechanism for heteroepitaxial growth in the InAs/Si system is studied by reflection highenergy electron diffraction, scanning
tunnelling microscopy, and photoluminescence. For certain growth conditions, InAs nanostructures are found to develop on the
Si surface immediately during the growth process in the course of molecular beam epitaxy. The range of substrate temperatures
that lead to formation of nanosized islands is determined. InAs quantum dots grown on a buffer Si layer with a silicon layer
of thickness 50 nm grown on the top produced photoluminescence lines at a wavelength of 1.3 μm at 77K and 1.6 μm at 300 K.
Fiz. Tekh. Poluprovodn. 33, 1066–1069 (September 1999) 相似文献
108.
M. V. Maksimov A. V. Sakharov V. V. Lundin A. S. Usikov B. V. Pushnyi I. L. Krestnikov N. N. Ledentsov P. S. Kop’ev Zh. I. Alferov V. P. Rozum 《Technical Physics Letters》1997,23(8):597-599
The luminescence properties of a GaN/Al0.1Ga0.9N double heterostructure grown by vapor-phase deposition from organometallic compounds are studied. When luminescence is observed
from the end, the radiation intensity shows a sharply defined threshold dependence on the pump density. The threshold excitation
density at T=77 K was ∼40 kW/cm2 and the wavelength of the stimulated emission was λ=357 nm. The long-wavelength shift of the emission line at high pump densities
may be attributed to renormalization of the band gap caused by many-particle interactions in the electron-hole plasma.
Pis’ma Zh. Tekh. Fiz. 23, 53–59 (August 12, 1997) 相似文献
109.
Wright RF Aherne J Bishop K Camarero L Cosby BJ Erlandsson M Evans CD Forsius M Hardekopf DW Helliwell R Hruska J Jenkins A Kopácek J Moldan F Posch M Rogora M 《The Science of the total environment》2006,365(1-3):154-166
The MAGIC model was used to evaluate the relative sensitivity of several possible climate-induced effects on the recovery of soil and surface water from acidification. A common protocol was used at 14 intensively studied sites in Europe and eastern North America. The results show that several of the factors are of only minor importance (increase in pCO(2) in soil air and runoff, for example), several are important at only a few sites (seasalts at near-coastal sites, for example) and several are important at nearly all sites (increased concentrations of organic acids in soil solution and runoff, for example). In addition changes in forest growth and decomposition of soil organic matter are important at forested sites and sites at risk of nitrogen saturation. The trials suggest that in future modelling of recovery from acidification should take into account possible concurrent climate changes and focus specially on the climate-induced changes in organic acids and nitrogen retention. 相似文献
110.
A. E. Zhukov A. R. Kovsh V. M. Ustinov A. Yu. Egorov N. N. Ledentsov A. F. Tsatsul’nikov M. V. Maksimov S. V. Zaitsev Yu. M. Shernyakov A. V. Lunev P. S. Kop’ev Zh. I. Alferov D. Bimberg 《Semiconductors》1999,33(9):1013-1015
The current dependence of the optical gain in lasers based on self-organized InGaAs quantum dots in a AlGaAs/GaAs matrix is
investigated experimentally. A transition from lasing via the ground state of quantum dots to lasing via an excited state
is observed. The saturated gain in the latter case is approximately four times greater than for the ground state. This result
is attributable to the fourfold degeneracy of the excited level of quantum dots. The effect of the density of the quantum-dot
array on the threshold characteristics is investigated. A lower-density array of dots is characterized by a lower threshold
current density in the low-loss regime, because the transmission current is lower, while dense quantum-dot arrays characterized
by a high saturated gain are preferable at high threshold gains.
Fiz. Tekh. Poluprovodn. 33, 1111–1114 (September 1999) 相似文献